The present invention relates generally to ink printers, the ink used in such ink printers, and the apparatus and method for feeding the ink into the printer.
Solid ink or phase change ink printers conventionally receive ink in a solid form, either as pellets or as ink sticks. A feed mechanism delivers the solid ink to a heater assembly, where the ink is melted into a liquid state for jetting onto a receiving medium.
Solid ink or phase change ink printers conventionally receive ink in a solid form and convert the ink to a liquid form for jetting onto a receiving medium. The printer receives the solid ink either as pellets or as ink sticks in a feed chute. With solid ink sticks, the solid ink sticks are either gravity fed or spring loaded through a feed channel of the feed chute toward a heater plate. The heater plate melts the solid ink into its liquid form. In a printer that receives solid ink sticks, the sticks are either gravity fed or spring loaded into a feed channel and pressed against a heater plate to melt the solid ink into its liquid form. U.S. Pat. No. 5,734,402 for a Solid Ink Feed System, issued Mar. 31, 1998 to Rousseau et al.; and U.S. Pat. No. 5,861,903 for an Ink Feed System, issued Jan. 19, 1999 to Crawford et al. describe exemplary systems for delivering solid ink sticks into a phase change ink printer.
A set of ink sticks for a phase change ink jet printer includes a plurality of ink sticks. Each ink stick is formed of a three dimensional ink stick body with a perimeter. Each of the ink stick bodies has one or more key elements formed in its perimeter. Each of the key elements has a uniform shape and size. The key elements are in different positions on the perimeter of each ink stick, and particularly the key elements of some of the ink sticks are on a different side of the ink stick than are the key elements on others of the ink sticks in the set. Corresponding keys on the perimeters of the openings through which the ink sticks are inserted into their appropriate feed channel exclude ink sticks of the set that do not have the appropriate perimeter key element.